Porta-crane

ABSTRACT

A truck crane for use on a vehicle frame that includes a support frame including a pair of spaced apart support members, with means for pivotally mounting the support members at substantially one end thereof between operative and inoperative positions. To obtain various positions an extension device is cooperatively associated with the support members and includes a pair of extension members, each extension member and a respective support member being interfitted one within the other and being slidable and longitudinally adjustable relatively to its support member, so as to be adjustable between extended and retracted positions. Bridging means interconnecting the extension members at the free end is provided with releasably interconnecting means for retaining the support members and the extension members in longitudinally aligned extended and retracted positions. 
     Hydraulic means is pivotally connected at one end thereof to the vehicle frame and at the opposite end pivotally connected to the support members, so as to support the support frame in selected operative positions. Winch means is contained on the vehicle, and cable means having a hook at one end extending over the bridging means and connected to the winch means at the opposite end thereof is utilized.

BACKGROUND OF THE INVENTION

The present invention relates to a truck crane and particularly to a truck crane that may be conveniently put into operation.

The portable crane in accordance with the present invention is pneumatically operated and compact for city street and expressway travel. This enables quick convenient and low cost travel to and from heavy lift sites which would normally take a larger piece of crane equipment such as flat-bed truck. Lifting equipment is usually slow running and awkward which hampers the natural flow of city traffic.

OBJECTS OF THE INVENTION

An object of the present invention is the provision of a truck crane which combines minimum clearance requirements with minimum encumbrance of the load space on the truck platform when the crane is inoperative.

Another object of the present invention is to provide a truck crane that may be manually assembled into operative position by the user.

Another object of the present invention is to provide a truck crane that may be secured to the rear of a vehicle and used for lifting considerable loads with a relatively lightweight vehicle.

Other objects and advantages of the present invention will become apparent as the disclosure proceeds.

SUMMARY OF THE INVENTION

A truck crane for use on a vehicle frame is disclosed that includes a support frame including a pair of spaced apart support members, with means for pivotally mounting the support members at substantially one end thereof between operative and inoperative positions. An extension device is cooperatively associated with the support members and includes a pair of extension members, each extension member and a respective support member being interfitted one within the other and being slidable and longitudinally adjustable relatively to it support member, so as to be adjustable between extended and retracted positions. Bridging means is provided for interconnecting the extension members at the free end thereof. Releasably interconnecting means for retaining the support members and the extension members in longitudinally aligned extended and retracted positions is utilized.

Hydraulic means is pivotally connected at one end thereof to the vehicle frame and at the opposite end pivotally connected to the support members, so as to support the support frame in selected operative positions. Winch means is contained on the vehicle having cable means with a hook at one end extending over the bridging means and connected to the winch means at the opposite end thereof, such that the support frame is adjustable in the operative position extending beyond the vehicle to the inoperative position in which the support frame is contained on the vehicle and the cable powered by the winch operates the hook in the operative position of the support frame.

BRIEF DESCRIPTION OF THE DRAWINGS

Although the characteristic features of this invention will be particularly pointed out in the claims, the invention itself, and the manner in which it may be made and used, may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part hereof, wherein like reference numerals refer to like parts throughout the several views and in which:

FIG. 1 is a diagrammatic side view of the truck crane in accordance with the present invention;

FIG. 2 is a side view similar to FIG. 1 showing the crane in its operative extended position; and

FIG. 3 is a rear view of the truck crane in its operative and extended position as illustrated in FIG. 2.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now to FIGS. 1-3, there is illustrated a truck crane 10 mounted with respect to a vehicle frame 12 illustrated diagrammatically. The crane 10 is mounted relative to the rear portion 14 of the vehicle 12 and is designed in a manner to be easily assembled and brought into operational use and includes a support frame 16 including a pair of spaced apart support members 18 that may be tubular and of metal of sufficient wall thickness to be able to withstand the loads applied thereto.

The support frame 16 is adapted, as seen in FIG. 1, to be in an inoperative position and fully contained within the framework of the flat open portion of the vehicle frame 12. Each support member has a front end 20 and rear end 22. Pivotally mounting means 25 is contained on the rear portion 14 for pivotally mounting the support frame 16 between the inoperative position illustrated in FIG. 1 to the operative position illustrated in FIGS. 2 and 3. The pivotally mounting means includes a pair of vertically extending spaced apart brackets 26 with a transversely extending shaft 28 extending between said bracket 26 and through the lower end 22 of each respective support member 18. The support brackets 26 further act as means for maintaining the support members 18 is laterally spaced relation to each other by limiting the lateral motion of the support members 18.

An extension device 30 is cooperatively associated with the support members 18 and includes a pair of extension members or jibs 32. Each extension member 32 and a respective support member 18 being interfitted one within the other and being slidable and longitudinally adjustable relatively to its support member 18 so as to be adjustable between the extended position illustrated in FIGS. 2 and 3 and the retracted position illustrated in FIG. 1. The extension members 32 may also be made of an appropriate size tubular member or solid bar stock, that is made from metal.

Bridging means 35 is provided for interconnecting the extension member 32 at the free end 34 thereof. The bridging means 35 may include a central bridging member 36 that extends transversely to the direction of the extension members 32 with downwardly extending side bridging members 38 that interfit within the free end 34 of the extension members 32. In this manner the support frame 16 is pivotally mounted at one end thereof and is easily adjustable and manually assembled to be adjusted both into the operative position of the crane 10 and bringing the extension members 32 into the extended position illustrated in FIGS. 2 and 3.

To retain the support frame 16 in its operative position, hydraulic means 40 is provided between the vehicle frame 12 and the support frame 16. The hydraulic means 40 includes a hydraulic device or cylinder 42 having a longitudinally extending arm 44 with a connecting arm 46 associated therewith. The connecting arm is pivotally connected to the vehicle frame 12 by means of a cross member 48 having outwardly extending rods or connecting members 50.

To maintain the extension members 32 relative to the support members 18 releasably interconnecting means 52 is provided and may include a sleeve or band 54 extending in telescopic relation to each support member 18. In the various extended and retracted positions the support members 18 and extension members 32 have associated therewith cooperating apertures that will be in alignment with each other. A fastener 56 is associated with each band 54 to extend within the aligned apertures to obtain a locking relationship therebetween. The fastener 56 may be threaded or the weight applied by the slidably extending extension members 32 and support members 18 may be sufficient to retain the fastener 56 in any selected position.

The extending rods 50 of the cross member 48 are secured to the bands 54 such that any force applied by the connecting arm 46 to the cross member 48 is in turn transmitted to the interconnecting means 52 which in turn is transmitted to the support frame 16 to retain the crane 10 in a selected position.

The hydraulic means 40 has a joint 60 at the lower end of the cylinder 42 and has a similar joint (not shown) at the coupling end between the connecting arm 46 and the cross member 48. These joints 60 are adapted to permit both angular rotation of the hydraulic means 40 as well as rotating motion to compensate for movement in the body of the vehicle 12 when weight by the load is applied thereto. The hydraulic means 40 further includes a pneumatic cylinder 62 contained within the rear portion 14 with hydraulic control lines 64 and 66 extending into the drivers portion of the vehicle 12 where controls are provided. A second pair of hydraulic lines 68 and 70 are connected through the valve 60 to the cylinder 42 in a conventional manner.

Winch means 72 is provided on the rear portion 14 and includes cable means 74 having a hook 75 at one end thereof adapted for gripping the load to be lifted by the crane 10. The winch may be operated from within the vehicle or externally thereof in a manner well known. Associated with the cable means 74 is a pulley 76 that is utilized to disconnect the cable 74 from its relationship with the load as desired.

In operation the operator of the vehicle 12 will also utilize adjustable securing means 78 which may be in the form of a chain 80 extending at one end to a post 82 rigidly mounted on the rear section 14 and at the opposite end to a ring clamp 84 that is firmly secured to one or both support members 18. The purpose of the adjustable securing means 78 is to further assist the hydraulic means 40 in maintaining the support frame in the operative position illustrated when the load is applied to the lift hook 75.

Accordingly, as described above the crane of the present invention is easily adjustable from its operative to inoperative positions and this adjustment is done manually in that the extension members 32 are extended outwardly from within the position illustrated in FIG. 1. In order to support the crane 10 in the position seen in FIG. 1 resting means 85 is provided and may extend upwardly from the rear portion 14 and engage the sleeve 54 and have a compressable head 86 to retain the support frame 16 in its operative position. When the user of the vehicle 12 reaches the vehicle or other object to be lifted or towed, the decision can be made as to what extent the extension members 32 may be moved outwardly with appropriate adjustment of the interconnecting means 52 such that the desired overhang past the rear of the vehicle can be selected.

The hydraulic means 40 is activated to retain the support frame 12 in the desired angular position with respect to the rear portion 14 of the vehicle 12. When this desired position is reached the adjustable securing means 78 can be utilized to further support the structure of the crane 10 when the load is applied by means of the hook 75.

Although an illustrative embodiment of the invention has been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to the precise embodiment, and that various changes and modifications may be effected therein without departing from the scope or spirit of the invention. 

I claim:
 1. A truck crane for use on a vehicle frame, comprising:A. a support frame including a pair of spaced apart support members, B. means for pivotally mounting said support members at substantially one end thereof between operative and inoperative positions, C. an extension device cooperatively associated with said support members, said extension device comprising a pair of extension members, each extension member and a respective support member being interfitted one within the other and being slidable and longitudinally adjustable relatively to its support member, so as to be adjustable between extended and retracted positions, D. bridging means interconnecting said extension members at the free end thereof, E. releasably interconnecting means for retaining said support members and said extension members in longitudinally aligned extended and retracted positions, F. said interconnecting means including:1. a band in telescopic relation to each said support member,
 2. cooperating apertures in each said support member and said extension member in alignment with each other when said extension members are in said extended and retracted positions, and
 3. a fastener associated with each band to extend within said apertures for obtaining a locking relationship therebetween,G. means for maintaining said support members in laterally spaced relation to each other, said maintaining means including a cross-member extending between said bands of said interconnecting means, H. hydraulic means pivotally connected at one end thereof to the vehicle frame and at the opposite end pivotally connected to said cross-member, so as to support said support frame in selected operative positions, I. said hydraulic means includes a cylinder connected to the vehicle frame at one end thereof and a longitudinally extending arm hydraulically powered by and extending from one end of said cylinder and coupled at its opposite end to said cross-member, said hydraulic means being connected to the vehicle frame and to said cross-member in a manner to permit rotating motion therebetween, J. winch means contained on the vehicle, K. cable means having a hook at one end extending over said bridging means and connected to said winch means at the opposite end thereof, such that said support frame is adjustable in the operative position extending beyond the vehicle to the inoperative position in which the said support frame is contained on the vehicle and said cable powered by said winch operates the hook in the operative position of said support frame, and L. adjustable securing means extending between the vehicle and said support frame.
 2. A truck crane as defined in claim 1, and further including a pulley connected with said cable between said hook and said bridging means.
 3. A truck crane as defined in claim 1, and further including wherein said adjustable securing means extending between the vehicle and the support frame is in the form of a chain so as to provide ease of adjustment in length thereof. 